This invention relates to high speed missiles that incorporate winged surfaces and particularly to the orientation of a two-dimensional inlet relative to the winged surface and missile body.
As is well known in the art, the inlet of a missile air breathing power plant must be judiciously located to reduce drag while satisfying packaging restriction and weight limitations. Such location takes into consideration the shock waves, flow angles, and other flow properties produced by the bow of the missile and the leading edge of the wing. Because of the high altitude requirements of some air breathing missiles, wings are utilized to generate the necessary lift characteristics. If two-dimensional inlets are integrated under the wings in a conventional downward turning orientation, the inlets will be effectively exposed to zero angle of attack conditions since the flow approaching the inlets must be aligned with the undersurface of the wings. However this orientation would not be totally satisfactory owing to the outwash produced by the undersurface of the wing and vehicle body. In such an orientation, the outwash flow would effectively subject the two-dimensional inlets to a yaw condition which, characteristically, would degrade inlet performance.
I have found that I can improve inlet performance by orienting it relative to the outwash angle induced by the wing and missile body such that the inlet sees an effective angle of attack rather than a yaw condition. This is a favorable situation since, in general, the performance of two-dimensional inlets is enhanced with increasing angle of attack.